The condition Lilly had was one she had since birth but was held off by her powers and when her powers were passed down to Cole it began affecting her and it is a hereditary condition
i like to think cole knows it's hereditary and just doesn't tell anyone, not even the finders or the ninja. he thinks he'll live his life to the fullest if everyone isn't aware that something can slowly tear his life off course. in the case that cole does face this sickness, lou is the one that has to tell them how long he's known about the risk














